The present invention relates to technologies on a resource assignment method, a resource assignment program, and a management computer which are suitable for a relational database management system.
A DBMS (: Database Management System) is a system for answering a query made into data stored in a database. In particular, a RDBMS (: Relational Database Management System), which is a system for managing a table-format database, is the most common as the DBMS. SQL (: Structured Query Language) is frequently used as a language for describing a query made into the stored data.
Addressing a large number of queries requires that the processing time needed for processing a query be shortened. As a result, conventionally, a parallel processing such as pipeline processing has been performed in the following way: A query processing is partitioned into a plurality of phases, and the individual processing phases are distributed among a plurality of nodes (i.e., computer resources), thereby implementing the parallel processing.
Incidentally, a distribution algorithm is important which is used for determining to which node the individual processing phases should be distributed. For example, in the technology described in “A Hierarchical Approach to Parallel Multi-Query Scheduling”, Joel L. Wolf, John Turek, Ming-Syan Chen and Philip S. Yu, IEEE Transactions on Parallel and Distributed Systems, 6(6): pp. 578-590, June 1995, the individual processing phases are distributed based on each type of statistical information which is stored in dictionary of the DBMS, and which is about the query that becomes the processing target.